Sea otters use stones and rocks to break open abalone shells in order to eat the flesh inside. a young sea otter observes other sea otters break open shells and thus learns how to perform this task. what type of learning did the young sea otter use to be able to perform this task?

The type of learning that the young sea otter used to be able to perform this task is social learning.

This means that the young otter learned what it is supposed to do from its surroundings - and what is surrounding it is its society of other otters. It is social learning because the otter didn't learn on its own that it needs to break open shells in order to eat what is inside, but rather it saw what the other otters were doing and thus learned it.